The present invention relates to a vehicle backward movement assisting apparatus during parking, and particularly, to a device for superimposedly displaying an indicator for assisting a steering wheel operation during parking operation on a monitor screen on which the rear of a vehicle is imaged.
Also, the present invention relates to a vehicle backward movement assisting apparatus during parallel parking (in tandem), and particularly, to an apparatus for assisting a steering wheel operation in the case where a vehicle is stopped in an inclined state with respect to a parking space so as to be parked in tandem.
Conventionally, there has been proposed an apparatus, which displays the rear view of a vehicle on a monitor screen when a target place becomes out of sight for a driver due to a blind spot of the vehicle during a backward movement of the vehicle. For example, Japanese Patent Publication No. 2-36417 discloses a vehicle rear monitor apparatus comprising a television camera for picking up an image of the rear of a vehicle, a monitor television for displaying the image picked up by the television camera, a sensor for outputting an information signal related to a steering angle of a wheel, and a circuit for generating a marker signal in accordance with the information signal from the sensor and superimposedly displaying a marker on a television screen. In this apparatus, data on the wheel steering angle and data on marker positions along the direction in which the vehicle moves backward, which corresponds to the steering angle, are stored in a ROM. A predicted backward movement locus of the vehicle in accordance with the steering angle at that time is displayed on the television screen as a series of markers superimposed on the image picked up by the television camera.
According to this apparatus, when the vehicle moves backward, the rear view of a road condition, etc. and the predicted backward movement locus of the vehicle in accordance with the steering angle are displayed on the screen of the monitor television, so that the driver is capable of moving the vehicle backward by operating the steering wheel while the driver watches the television screen without turning the driver""s head backward.
However, when the above-described conventional apparatus is used in a parallel parking or a lateral parking, there are problems as follows: in the case of parallel parking, it is difficult for the driver to determine the timing to turn the steering wheel and the steering amount, and in the case of lateral parking, it is difficult for the driver to determine what amount the vehicle is to be moved backward and the steering amount for the completion of parking. On the other hand, when the driver can know the angle relation of the vehicle with respect to a target parking space at the time of starting the parking operation, it is possible to provide a preferable guide display in parallel parking or lateral parking based on the information.
When performing parallel parking, for example, the vehicle is stopped in an inclined state with respect to a parking space and advanced into the parking space at an appropriate steering angle. Further, the steering wheel is returned in the reverse direction to guide the vehicle to a target parking position. However, in the conventional rear monitor apparatus, there is a problem in that when the driver looks only the rear view and the predicted backward movement locus of the vehicle on the television screen, it is difficult for the driver to determine what degree of steering angle the vehicle is to be advanced into the parking space at and where the steering wheel is to be returned, whereby parallel parking can not be sufficiently assisted.
Also, in the case where the vehicle is stopped for parallel parking, the degree of the angle of the vehicle with respect to a parking space depends on the habit of each driver. Therefore, it is difficult to perform the steering assist appropriate to each driver.
The present invention has been made in view of the above problem. Accordingly, an object of the present invention is to provide a vehicle backward movement assisting apparatus for displaying a steering assist guide with which a driver can easily comprehend a steering rate and time frame, a steering amount and an amount to be moved backward in parking.
Another object of the present invention is to provide a vehicle backward movement assisting apparatus capable of guiding a steering rate and a steering amount which are appropriate to each driver in parallel parking.
In order to achieve the above objects, a vehicle backward movement assisting apparatus during parking operation according to claim 1 is characterized by comprising: a camera for picking up the rear view of a vehicle; a monitor disposed at a driver""s seat; a recognizing means for recognizing a start of turn of the vehicle; a detecting means for detecting a turn angle of the vehicle after the start of turn; means for indicating an acquisition of a turn angle for indicating a timing for detecting the turn angle to the means for detecting a turn angle; and means for controlling the monitor for displaying an image from the camera on the monitor while the vehicle is moving backward, and for superimposedly displaying on the monitor a guide display for assisting the vehicle drive during parking, and a guide display based on the turn angle detected by the means for detecting a turn angle.
The means for recognizing the start of a turn to a vehicle may be preferably composed of: means for detecting the rotation speed difference between a right wheel and a left wheel, a vehicle speed sensor and a steering angle sensor, or a dedicated button. The means for detecting a turn angle may be preferably composed of: a yaw rate sensor, the steering angle sensor and a travel distance sensor, or a geomagnetism sensor. The means for indicating an acquisition of a turn angle may be preferably composed of a shift lever or a dedicated button.
The guide display is one for parallel parking may include: a parallel parking guide line displayed on the monitor screen in accordance with the turn angle detected by the means for detecting a turn angle; a vehicle space mark movingly displayed along on the parallel parking guide line on the monitor screen in accordance with the steering angle of the steering wheel; and an eye mark which is fixedly displayed at a predetermined position of the monitor screen and guides a return point of the steering wheel.
A vehicle backward movement assisting apparatus during parallel parking operation according to claim 6 of the present invention comprises: a camera for picking up the rear view of a vehicle; a monitor disposed at a driver""s seat; a steering angle sensor for detecting a steering angle of a steering wheel; means for controlling a display, for displaying the image by the camera on the monitor while the vehicle being moved backward, and for superimposedly displaying on the screen of the monitor a guide display for assisting the vehicle drive during parking operation; and a first switch and a second switch which are disposed at the driver""s seat of the vehicle, and by which the moving guide display on the screen of the monitor is moved in parallel and rotated, respectively, characterized in that: the moving guide display includes a parallel parking guide line and a vehicle space mark displayed so as to be moved along on the parallel parking guide line in accordance with the steering angle of the steering wheel detected by the steering angle sensor; and the fixed guide display includes an eye mark, which is fixedly displayed at the predetermined position of the screen of the monitor and which guides a return point of the steering wheel; and the means for controlling a display learns and stores the past rotation angle of the moving guide display made by the second switch and represents the moving guide display on the screen of the monitor at the stored rotation angle.
In the apparatus, the image of the rear of a vehicle, which is picked up by the camera when the vehicle is moved backward, is displayed on the monitor, and the moving guide display and the fixed guide display are superimposedly displayed on the monitor screen as the guide displays during parallel parking operation. The past rotation angle of the moving guide display by the second switch is learned and stored, and the moving guide display is represented on the monitor screen at the stored rotation angle. That is, the moving guide display appropriate to a driver is provided.
A vehicle backward movement assisting apparatus during parallel parking operation according to claim 7 of the present invention, in the apparatus according to claim 6, comprises the steps of: operating the second switch in the stop position of a vehicle to adjust the inclination of a parallel parking guide line and the inclination of a vehicle space mark to a target regarding a parking space on the monitor screen; operating the first switch to superimpose the parallel parking guide line on the target regarding the parking space on the monitor screen; returning a steering wheel for superimposing the vehicle space mark on the parking space; moving the vehicle backward while retaining the steering wheel at the position; stopping the vehicle at the position where the eye mark is superimposed on the parking space; moving the vehicle backward during a static turn so that the steering angle becomes maximum in a reverse direction; and appropriately performing parallel parking of the vehicle at the parking space.
In the apparatus, at the stop position of the vehicle, the second switch is operated until the inclination of the parallel parking guide line and the inclination of the vehicle space mark are adjusted to the target regarding the parking space. Then, the first switch is operated until the parallel parking guide line is superimposed on the target regarding the parking space. Further, the steering wheel is returned to where the vehicle space mark is superimposed on the parking space, and the vehicle is moved backward while holding the steering wheel in the state. When the eye mark is superimposed on the target point, next, the position is recognized to be a return point of the steering wheel, resulting in stopping the vehicle. When the vehicle is moved backward during a static turn so that the steering angle becomes maximum in a reverse direction, the vehicle is appropriately parked in parallel at the parking space.
A vehicle backward movement assisting apparatus during parallel parking operation according to claim 8, in the apparatus according to claim 6 or 7, comprises a right-or-left selection switch which is disposed at the driver""s seat of the vehicle, for selecting one of a left parallel parking and a right parallel parking, in which the means for controlling the display represents on the monitor screen the moving guide display and the fixed guide display for the parallel parking selected by the right-or-left selection switch.
In the apparatus, when one of the left parallel parking and the right parallel is selected by the right-or-left selection switch, the moving guide display and the fixed guide display used for the selected parallel parking are displayed on the monitor screen.
In a vehicle backward movement assisting apparatus during parallel parking operation according to claim 9, in the apparatus according to claim 6 or 7, the means for controlling a display represents the moving guide display and the fixed guide display used for one of a right parallel parking and a left parallel parking with a high priority on the monitor screen, thereafter the means judges whether the direction of parallel parking is a right one or a left one, based on the steering angle detected by the steering angle sensor, and further in the case where the parallel parking is performed in a direction different from that in case of the moving guide display and the fixed guide display displayed with a higher priority, the moving guide display and the fixed guide display of the other direction are displayed on the monitor screen.
In the apparatus, first, the moving guide display and the fixed guide display used for one of the right parallel parking and the left parallel parking are displayed with a high priority on the monitor screen. Thereafter, whether the direction of parallel parking is a right one or a left one is judged based on the value detected by the steering angle sensor. In the case where the parallel parking is performed in a direction different from that in case of the moving guide display and the fixed guide display displayed with a higher priority, the apparatus changes to the moving guide display and the fixed guide display of the other direction are displayed on the monitor screen.
A vehicle backward movement assisting apparatus during parallel parking operation according to claim 10, in the apparatus according to claim 6 or 7, comprises a yaw rate sensor for detecting the yaw rate of a vehicle, in which the means for controlling a display judges whether the direction of parallel parking is a right one or a left one in accordance with the angle change of a vehicle in a predetermined time required for stopping for performing parallel parking, based on the yaw rate detected by the yaw rate sensor, and the moving guide display and the fixed guide display of parallel parking in the judged direction are displayed on the monitor screen.
In the apparatus, whether the direction of parallel parking is a right one or a left one is judged in accordance with the angle change of a vehicle in the predetermined time required for stopping the vehicle for performing parallel parking, based on the yaw rate detected by the yaw rate sensor. Then the moving guide display and the fixed guide display of parallel parking in the judged direction are displayed on the monitor screen.